This is a note to let you know that I've just added the patch titled
cdc-acm: do not reset notification buffer index upon urb unlinking
to the 4.18-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
cdc-acm-do-not-reset-notification-buffer-index-upon-urb-unlinking.patch
and it can be found in the queue-4.18 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From dae3ddba36f8c337fb59cef07d564da6fc9b7551 Mon Sep 17 00:00:00 2001
From: Tobias Herzog <t-herzog@xxxxxx>
Date: Sat, 22 Sep 2018 22:11:10 +0200
Subject: cdc-acm: do not reset notification buffer index upon urb unlinking
From: Tobias Herzog <t-herzog@xxxxxx>
commit dae3ddba36f8c337fb59cef07d564da6fc9b7551 upstream.
Resetting the write index of the notification buffer on urb unlink (e.g.
closing a cdc-acm device from userspace) may lead to wrong interpretation
of further received notifications, in case the index is not 0 when urb
unlink happens (i.e. when parts of a notification already have been
transferred). On the device side there is no "reset" of the notification
transimission and thus we would get out of sync with the device.
Signed-off-by: Tobias Herzog <t-herzog@xxxxxx>
Acked-by: Oliver Neukum <oneukum@xxxxxxxx>
Cc: stable <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/usb/class/cdc-acm.c | 1 -
1 file changed, 1 deletion(-)
--- a/drivers/usb/class/cdc-acm.c
+++ b/drivers/usb/class/cdc-acm.c
@@ -354,7 +354,6 @@ static void acm_ctrl_irq(struct urb *urb
case -ENOENT:
case -ESHUTDOWN:
/* this urb is terminated, clean up */
- acm->nb_index = 0;
dev_dbg(&acm->control->dev,
"%s - urb shutting down with status: %d\n",
__func__, status);
Patches currently in stable-queue which might be from t-herzog@xxxxxx are
queue-4.18/cdc-acm-correct-counting-of-uart-states-in-serial-state-notification.patch
queue-4.18/cdc-acm-do-not-reset-notification-buffer-index-upon-urb-unlinking.patch
